An effort to extend California’s signature program for reducing greenhouse gas emissions to combat climate change cleared the California Legislature on Monday, sending the deal to Gov. Jerry Brown’s desk.

Senate Pro Tem Kevin de León called AB 398, which cleared the necessary two-thirds threshold in both houses, a “legislative unicorn” that brought together an unusual coalition of business organizations and environmental groups, among others rarely aligned at the Capitol. After weeks of intense negotiations, eight Republican legislators voted for the measure to ensure its passage.